Partial discharge pattern recognition based on Transient Earth Voltage for 10 kV switchgear in smart grid

Partial discharge (PD) measurement is a promising method for condition assessment of insulation systems in smart grid. Conventional PD measuring systems have some difficulties in the measurements especially under on-line and noisy conditions. There is a growing tendency to use new measuring systems for the detection of PD pulses in 10 kV switchgears. In this paper, a new PD detection method based on Transient Earth Voltage (TEV) has been proposed. An efficient sensor was employed to detect PD pulses. The TEV sensor was implemented on a 10 kV switchgear and the TEV signals of three kinds of discharge were recorded and analyzed. The distribution characteristics of the signals were studied to achieve the pattern recognition. Finally the result of pattern recognition based on TEV signals was discussed. The result shows that the three kinds of discharge can be recognized through the spectrograms.